1. Technical Field
The present invention relates to a vibrating element and a manufacturing method for the same, a gyro sensor utilizing the vibrating element, an electronic apparatus and moving object or the like having the vibrating element incorporated therein.
2. Related Art
For example, a vibrating element utilized in a gyro sensor is generally known. If angular velocity motion is applied to the vibrating element, a Coriolis force acts to change the direction of vibration of a vibrating arm for driving. A new force component is generated in a specific direction corresponding to the Coriolis force. This force component causes motion of a vibrating arm for detection. Thus, an output signal corresponding to the force component is outputted from the vibrating arm for detection.
The main body of the vibrating element can be sliced out of a material, for example, a piezoelectric material. In slicing the material, a mask is arranged on a face side and a back side of the material. When a misalignment occurs between the masks, the lateral sides of the vibrating arm for driving cannot stay orthogonal to the face side and the back side and become inclined. As a processing error thus occurs in the cross-sectional shape of the vibrating arm for driving, the vibrating arm for driving cannot vibrate within a prescribed imaginary plane and vibrates in an imaginary plane that is inclined from the prescribed imaginary plane. Thus, so-called slant vibration occurs. Such a phenomenon is called vibration leakage, and a leak vibration component is superimposed on the force component in an output signal from the vibrating arm for detection. Consequently, the S/N ratio of the output signal is deteriorated. That is, a signal to be noise is outputted from the vibrating element in the state where angular velocity motion is not inputted. In JP-A-2008-267983, detection electrodes are partly removed in order to eliminate the leak vibration component. However, such elimination of detection electrodes induces reduction in signal intensity. Therefore, the S/N ratio of the output signal cannot be improved as expected.